The effect of the main production parameters of sintering and subsequent deformation of sintered billets on the structure and level of oxidation of steel after hot forming is studied. It is shown that use of an activating addition (30% boron and 70% nickel powder) in order to protect the sintered material form oxidation during heating for forming is highly efficient.Hot forming of porous billets is an alternative with respect to liquid-phase sintering for preparation of individual billets from high-speed steel powder. At the same time it provides the possibility of forming the fine-grained structure of the material, that is close to the characteristics of high-speed steels prepared by hot isostatic compaction technology in the solid phase temperature range followed by forging, and (or) rolling.High-speed steel with the use of hot forming of porous billets was obtained for the first time by the authors in [1] from turnings as the original material. In its properties such steel is not surpassed by standard (cast and deformed) steel of a similar composition. At the same time use of hot forming for preparing a tool billet from atomized powders of high-speed steel, as has been shown by the authors in [2], apart from the apparent advantages is connected with difficulties that are caused primarily by the high chemical affinity of the main alloying elements towards oxygen. An oxide film at the surface of particles formed during heating for forming prevents formation of a high-quality contact surface between particles due to a lack of consolidation of them. In addition, particles of unreduced oxides in powder steels are stress concentrators that markedly reduce the toughness and ductility of the material. In view of this in the present work a study has been made of the effect of production parameters for sintering and subsequent treatment of sintered billets on the structure and degree of oxidation of steel after hot forming and methods have been developed for reducing its degree of oxidation.Specimens were compacted from steel R6M5K5 powder fraction −400 μm, and also from a mixture of it with 1% activating addition (30% B and 70% Ni) [3]. High-temperature vacuum sintering was performed at 1180-1220°C. After sintering specimens of the first composition had an average density of 6.7 g/cm 3 , and those sintered with an activator had a density of 7.3 g/cm 3 .In order to reduce the possibility of penetration of oxygen through open pores in a billet sintered without an activating addition, before hot forming they were treated according to recommendations in [4] by one of the following methods: impregnation with a paraffin-graphite mixture, coating of the surface with molten glass, and tumbling. After treatment specimens were heated in a silicon carbide furnace in an argon atmosphere to 1050-1180°C for 10 min and subjected to hot forming in a closed die in a cranked press. The heating temperature for forming was selected from the consideration that heating below 1120-1150°C is insufficient in order to consolidate particles of ...